'His stupidity will get us all killed,' one Twitter user wrote.

North Korea Only "Understands One Thing", Trump Tweets After Nuclear TestWochit

US President Donald Trump referred to North Korean leader Kim Jong-un as "Rocket Man" in a taunting tweet early Sunday morning (17 September) and Twitter furiously slammed him for it. Amid a flurry of retweets, Trump asserted in a post that North Korean citizens have been queuing up for petrol before the latest round of UN sanctions against Pyongyang hits supplies.

Trump wrote: "I spoke with President Moon [Jae-in] of South Korea last night. Asked him how Rocket Man is doing. Long gas lines forming in North Korea. Too bad!"

The White House said that Trump and Moon discussed the hermit kingdom's recent alarming intercontinental ballistic missile (ICBM) launches in a call on Saturday and declared their commitment "to continuing to take steps to strengthen deterrence and defense capabilities and to maximize economic and diplomatic pressure on North Korea."

Twitter, on the other hand, immediately blasted the president over his "childish" name-calling of the North Korean leader saying, "You really think taunting a hostile nuclear power on Twitter is a good idea!?"

"This is among the more shockingly depraved and callous comments a world leader has made about a vulnerable populous recently. #Shame", Lord of the Rings actor Sean Astin tweeted.

Adam Best wrote: "Rocket Man. Retweeting memes. Bragging about his value. Trump wants to be a third-world dictator but he's more like a third-grade dictator."

Many people also responded to Trump's comments with a slew of Elton John-themed comments, jokes and memes.

"Why did you ask the President of South Korea about Elton John?" one person tweeted. Another wrote: "Does that make Donald Trump 'Tiny Dancer'?"

"Sorry Trump, but Elton John is the only "Rocket Man" we acknowledge," one person chimed.

However, several people expressed serious concerns over Trump's latest slew of disturbing retweets and his mocking of the North Korean leader.

"I gather Kelly isn't with Trump today so we are seeing the real thing - which is incredibly disturbing and frightening for our country," Amy Siskind tweeted, referring to White House Chief of Staff John Kelly.

I spoke with President Moon of South Korea last night. Asked him how Rocket Man is doing. Long gas lines forming in North Korea. Too bad!